What is it comprised of?

The digestive system of the horse is made up of the mouth, esophagus, stomach, small intestine and large intestine, which is made up of cecum, large colon, small colon and the rectum.  The whole digestive system of the horse is around 30 metres long, mostly comprised of intestines.

How does the process work?

When a horse eats, it takes food in through it's mouth.  If it is being fed a already chopped up feed, like chaff and grain it will take it up using it's lips, if it is eating grass it will use it's front teeth or incisors to chop the grass from the ground first.  Food is then moved back in the mouth by it's very large tongue - it is roughly the size of an adult female's forearm!  It is ground up by the back teeth using the premolars and molars before being swallowed.  The muscles used are the big masseter muscles on the cheeks.

Once swallowed the feed moves through to the esophagus which is between 1.2 - 1.4 metres in length which carries the food through to the stomach.  Horses are unable to vomit due to a muscular ring called the cardiac sphincter, which is very strong and well-developed and also placed at an angle.

Horses have very small  stomachs for their size, which is why they are most suited to grazing quite continuously (up to 16 hours per day) and when they have access to vast amounts of grazing land will travel long distances to choose what they forage on.  We keep horses in a much more intense environment so have to balance their diets as best as we can.  Anyway, off track a little because if I start yapping on about nutrition then this post may never end!  So horses have very small stomachs that can fit around 15 litres in them at a time.  It is most effective when 1/2 this volume approximately is being used because the stomach will empty when it is 2/3rds full regardless of whether the horse has processed the food or not.  It is better to have access to continuous forage, like hay if there is no pasture and if you need to bulk up with a hard feed for whatever the reason (like adding supplements) then you should make them small feeds.  When the feed leaves the stomach it exits through the pyloric valve, which controls the flow of the food out of the stomach.

The next part of their digestive process occurs in the small intestine.  This alone is between 15 - 21 metres in length.  It is where most of the digestive action happens and where most of the nutrients are absorbed by the body, including, proteins, simple carbohydrates, fats and the fat soluble vitamins A, D & E.  Horses do not have a gall bladder so bile flow is constant.  The bile from the liver is what helps to digest fats.  Anything left over then moves into the large intestine for the body to process.

As I mentioned before, the large intestine is broken into a few more sections.  The cecum is the 1st section of the large intestine, commonly referred to as the 'hind gut'.  It is about 1.2 metres long and holds 26 - 30 litres. It contains bacteria that use fermentation to digest what is left.  A horse cannot cope with too sudden a change in their diets because of the bacteria that live in the cecum.  The bacteria need time to adjust and modify in order to be able to process the new feeds.  If it cannot be broken down properly in this area then a horse is likely to colic.

The large colon is between 3 - 3.7 metres in length and can hold up to 76 litres of semi liquid matter.    The main purpose of the large colon is to absorb carbohydrate.  The large colon is a common place for a horse to get an impaction colic because it is a very twisty due to it's length, also the twisted bowel colic would likely occur here.

The small colon is also 3 - 3.7 metres in length.  It can only hold around 19 litres in comparison.  This is where the majority of water in a horses diet is absorbed and is where the balls of faeces are formed prior to expulsion.

The rectum is only around 30 centimetres in length and acts only as a holding chamber before the horse expels the left over waste via the anus.

Common Digestive System Disorders

Some signs that your horse's digestive system might not be working properly are:

  • Diarrhea
  • Constipation
  • Drooling
  • Loss of Appetite
  • Changes to faeces
  • Abdominal pain
  • Loss of gut sounds
  • Bloating
  • Dehydration

As you would likely guess by now, the digestive system is super important so referral to a qualified vet at any of these signs or changes is crucial so you can get a correct and accurate diagnosis and treatment for any of these symptoms.  It may be as simple as the horse needs a dental but could be as crucial as your horse might require surgery if appropriate.  Either way, any problems with the digestive system should be treated as serious.

Diarrhea can have many causes.  It can be caused by bacterial infections, malabsorption of nutrients or a viral infection - or may simply be because they are on very fresh, rich or wet pick in the paddock.  Either way - refer to a vet - especially if it is a sudden change and you don't know the cause!

Colic in horses is a common digestive disorder. It can be caused by so many different variables: change in diet, a stressful event, a foreign matter being ingested, dehydration and so on.  The signs of it are usually that a horse cannot defecate, a decrease in appetite, a rise in temperature and loss of gut sounds.  Your horse may also want to get away from the pain and discomfort in their abdomen so will likely look at their stomach, paw at the ground or want to repeatedly roll.  The last thing that you want them to do is to roll because it can then twist the intestines which is regularly fatal for the horse.  You should be contacting the vet for any suspected cases of colic so that your horse can be treated appropriately.  The sooner you can get them help the more likely their survival is depending on what has caused the colic.

Parasites can be another common cause of digestive system upset.  It is easy for the body to be invaded by parasites through the mouth.  It is important to have a good worming program in place for your horses so they cannot develop a resistance therefore allowing parasites to enter their system more easily.  Signs that your horse may have a parasitic infection are:

  • Scratching their tail
  • Messy anus
  • Malformed faeces
  • Weight loss
  • Dull coat
  • Loss or increase in appetite
  • Bloating

There are many products on the market to assist with controlling parasites in your horses and also as always your vet is a great resource to ask on what are the best control methods you should use in your particular case.

Stomach ulcers are also a problem in horses - I don't know now who said it but, "It is not a question of if your horse has ulcers - but when they get ulcers".  I have written a whole post on Ulcers that you can read here.

There are many other factors that can affect your horses digestive system but the bottom line is - your horse has a small stomach so should have access to small feeds and forage regularly as well as a fresh supply of water at all times.  A resting horse in Winter can drink up to 20 litres of water per day!  Don't skimp on it - and make sure it's fresh - taste it yourself!  And, if anything seems not right with your horses digestive system then make sure you refer to the vet.

My aim here is to give you a brief overview of the skeletal system.

What is the Skeletal System made up of?

Most horses have 205 bones in their body.  This can vary slightly as Arabians can have 1 set less of ribs due to a shorter back.  Also the amount of coccygeal or tail bones may vary slightly.  The skeleton is made up of long, short, flat and irregular bones. The long bones are typically found in the limbs - they act like levers and store minerals.  Short bones are found in the fetlock, knee and hocks and their job is to be shock absorbents.  Examples of flat bones are the ribs and scapula and these are there to protect.  And irregular bones protect the central nervous system and are found in vertebrae.  The bones are connected to each other via ligaments and the muscles are connected to the bones via tendons.  A bone is covered in a tough outer layer called the periosteum and at the site of joints there are little bursae sacs filled with synovial fluid which act as cushioning and lubricant of the joints.

What it does?

The function of bones is to provide the body's framework, protect vital organs and protect soft tissue.  Bones also are levers, store minerals and are where red blood cells are formed.  The muscles act to support the entire skeleton of the horse and the stronger these are the better supported the horse's skeleton is.

What can happen to the skeletal system that affects the horses performance?

Horses can suffer from degenerative joint disease (DJD)- typically osteoarthritis which will cause the joints and bones to wear and this will cause ...continue reading

In this post I want to discuss baseline fitness on your horse. It doesn't matter what sport you choose to take part in with your horse, they should be fit enough for the job they need to do.  Obviously different sports require different fitness levels as for example racing has different fitness requirements to dressage, and endurance different requirements to polocrosse!  Not to mention every other imaginable horse sport in between!!

It is not fair on your horse to pull him out of the paddock once a month, then sit on him and ask him to perform for you at any level for any period of time.  I would say that this kind of horse has the physical fitness that would allow him to undertake a very small amount of work, like potentially a walk and trot for a 1/2 hour.  If that is all you desire then that would be suitable.  However, most of us like to use our horses more often than this or for a longer time period, potentially at higher speeds.  So we need to be fair and adjust their training and increase their fitness so as to suit their job.

One little article is not going to be able to cover each discipline.

Firstly, the reason that you want to get some baseline fitness for your horses is ...continue reading

Cooling Off Techniques for Horses at Competition

I was prompted to write a series of articles on the correct strapping of the horse after attending competitions and witnessing competitors strapping their horses in very unusual ways! After speaking to some of these people, I have come to realise that riders have not been specifically taught how to strap their horse. ...continue reading

There is a lot of information kicking around the internet at the moment relating to stomach ulcers in horses.  It is not a matter of if a horse has ulcers - it is more likely that sometime in your horses life they will suffer from them.

A horse cannot get rid of ulcers on their own especially in the conditions that we keep them in. They do not have the luxury of roaming large distances and choosing which type of food they eat.  We keep them in controlled environments.  If they are on pasture it consists of only a small range of grasses and sometimes no access to trees or roots or even quality soil to chomp on when they feel something lacking in their diet.  These are the behaviors of wild horses that know what to eat for medicine or de-worming etc.  If they are hard fed it will usually consist of some hay - and regardless of the type of hay you feed, the nutrients that can be found in this ...continue reading

 A program for your horse's overall health

Horse health
Horse health

I am often asked by my client's what is a good program to put their horse's on for their entire health.  For the most part this can be a tricky question to answer but I will put my thoughts out there for you all.  You do not always have to agree with me and I would love to hear your individual thoughts on the matter:

Most horse owner's know that they must have a worming program, feet program and teeth program but it will vary for each individual horse and their own needs, the same as it does for humans.

As people we are reminded by our dentist to visit every 6 or 12 months, but if you wear braces that might be more like a 6 - 8 week cycle!  We are told to brush our teeth each day morning and night and again this is a variable factor for each individual!  As a human we know when we Continue reading

If you've been following along with my Blogs, I have started going through the 11 systems of the horse.  This blog is about the all important muscular system

Firstly, what is the muscular system made up of?

Around 60% of a horse's total body weight is made of muscles and tendons!  The muscular system is made up of muscles, fascia and tendons.  The muscle are comprised of about 70% water and the other 30% is made up of fibres and nerves.  Muscles can also stretch up to 90% and the tendons about 10% and these contracting and releasing create the movement of the skeleton and therefore the movement of the horse.  The muscles are connected to the skeletal system by the tendons.

What kind of injuries can muscles incur?
Muscles can suffer from overuse, overstretch and then tear or incorrect work preparation.  Poor nutrition, poor conformation or a structural imbalance can cause injuries to muscles.  They can also suffer from a blow out.

...continue reading

The 1st system I listed in the Blog 'What Are the 11 Systems of the Horse' was the integumentary system - or the skin, hair and hooves.  In this issue I would like to discuss this system further.  I will explain what it is, what it does and how it relates to massage.

Firstly; what is the integumentary system comprised of?
Horse Hair
The skin is made of 3 basic layers.  The hypodermis, which is the innermost layer, the dermis and the epidermis.  The hair and hooves are also part of this system.

The hypodermis is made up of connective tissue that allows the skin to glide over the muscles.  It is a cushioning layer between the muscles and the skin.  There are large blood vessels that supply the skin in this layer.  The dermis and the hypodermis also contain nerve endings.

The dermis is the thick layer containing nerve ends, hair follicles, sebaceous (oil) and sweat glands, blood and lymphatic vessels.  It is attached to the hypodermis by collagen fibres that give the skin elasticity. ...continue reading

Many horse owner's include lucerne either in the form of hay or chaff in their horse's everyday diets.   The reason they feed it is usually because the horse likes it and it is what they have been taught is a good feedstuff for horses.  It provides good roughage and bulk for their horse's and also smells nice and sweet.  That is because it is sweet!  It is loaded with sugars and great to help provide your horse with extra warmth and energy.  Lucerne is also high in protein and calcium.  It is useful to feed it at a competition where your horse is using a lot of energy and needs the extra usable fuel.  Examples of this would be at endurance rides, polocrosse or any other high energy burning horse sport.  It is also useful to help growing youngsters that need to put extra fuel into correct growth.  Does this make lucerne a suitable every day feed? ...continue reading